Mechanical Properties of 30 Year-Old Naturally Corroded Steel Reinforcing Bars

The present paper investigates the mechanical response of more than 120 corroded reinforcing bars extracted from a real bridge after 30 years in service. Corrosion was quantified using gravimetric and 3D-laser scanning measurements. An expression to relate the average and critical corrosion levels was found, the latter being the main parameter governing the capacity of corroded bars. Whereas the strength of the material was not affected by corrosion, the ultimate strain decreased sharply. However, strains were not only affected by cross-sectional reduction but also by the shape of the critical pit and necking at failure.